The present disclosure herein relates to semiconductor devices and, more particularly, to three-dimensional nonvolatile memory devices.
In order to satisfy a demand for excellent performance and low price, it is required to increase a degree of integration of a semiconductor device. In the case of a semiconductor memory device, since the integration degree is an important factor which determines a product price, higher integration degree is particularly required. In the case of a typical two dimensional or planar semiconductor memory device, the integration degree is mostly determined by an area occupied by a unit memory cell. Therefore, the typical memory device is greatly affected by a level of a technology for forming a micro pattern.
Recently, a three-dimensional semiconductor memory device provided with three dimensionally arranged memory cells has been proposed. However, for mass production of the three-dimensional semiconductor memory device, it is required to develop fabricating technology so that manufacturing costs per bit may be lower than that of the two-dimensional semiconductor memory device with reliable production properties.